Link to a page where the issue can be seen: hidden link
I expected to see:
The custom fields screen
Instead, I got:
Stuck loading bar and the following Javascript errors:
Uncaught TypeError: Unable to process binding "if: function(){return (itemsToShow().length > 0) }"
Message: Unable to process binding "foreach: function(){return itemsToShow }"
Message: Unable to process binding "click: function(){return ToolsetTypes.Utils.Pointer.show($element) }"
Message: $this.pointer is not a function
at Object.showPointer [as show] (pointer.js:41)
at click (eval at parseBindingsString (knockout-3.4.0.js:68), <anonymous>:3:92)
at knockout-3.4.0.js:103
at init (knockout-3.4.0.js:89)
at init (knockout-3.4.0.js:103)
at knockout-3.4.0.js:72
at Object.w (knockout-3.4.0.js:39)
at knockout-3.4.0.js:71
at Object.q (knockout-3.4.0.js:11)
at m (knockout-3.4.0.js:71)
An issue like this is normally due to a plugin conflict. What I would recommend that you do is to temporarily disable all your non-toolset plugins and check again to see if the issue still remains.
Given that the issue is being caused by the Enable jQuery Migrate Helper plugin, there isn't much we can do about it.
What you can do is to alternate between using the Enable jQuery Migrate Helper plugin when you're not setting up your Toolset custom fields. I'm correct to assume that this issue only occurs when you're on the screen to create the custom fields themselves.
My best advise is to wait until your theme author provides a fix for the theme.